I tend to stager (become unbalanced) while walking. I get sudden dizziness with palpitation. Blood tests, heart condition, ct scan of head (by cardiologist and md physicians) are normal. What can be my problem at an age of 50 yrs. I have anxiety and panic disorder also. At present I take prothiaden 50 and etizolam 25 twice a day and beta cap 20 once a day for palpitation. Bp is 110/70 and sugar 100-140 (fb & pp) kindly help.